Currently, in the fabrication of a panel, an electrical detection needs to be performed on a display substrate or the assembled panel before bonding a driving chip, that is, a signal detecting device inputs a signal into the panel through a terminal of a signal line of the panel, so as to detect whether a defect exists in the panel.
In the process of performing the electric detection, a shorting bar is generally used to lead a signal line to a relatively spacious region, and a detecting probe is connected to a terminal of the shorting bar. Since intervals between terminals of the shorting bars may be relatively large, demand on accuracy of the detecting probes is relatively low. After the electric detection is finished, the shorting bar circuits need to be cut off or removed by way of laser cutting, and meanwhile, it is necessary to use a corresponding detecting apparatus to detect the areas of the shorting bar circuits, so as to ensure that the shorting bar circuits in the panel are completely cut off.
FIG. 1 is a schematic diagram of a structure of a detecting apparatus in the prior art, and FIG. 2 is a schematic diagram of a detecting image generated by an image generating unit in the detecting apparatus shown in FIG. 1. As shown in FIGS. 1 and 2, the detecting apparatus comprises: a base 3, an image generating unit 6 (which is generally a camera) and a detecting unit 7. Positioning pillars 4 for supporting a lower surface of a panel 1 and positioning the panel 1 are provided on the base 3. The image generating unit 6 is arranged above the panel 1, and is connected to the detecting unit 7. The detecting process of the detecting apparatus is as follows. At first, the image generating unit 6 emits detecting light 5, which lasts for a relatively short time, onto the area of a shorting bar circuit 2 on the panel, at this point, the shorting bar circuit 2 remaining on the panel will reflect the detecting light 5 to the image generating unit 6, while for the area of the panel where no shorting bar circuit 2 remains, the detecting light 5 will be transmitted to the base 3 directly and absorbed by the base 3. Then, the image generating unit 6 generates a detecting image of the area of the shorting bar circuit 2 on the panel according to the received reflected detecting light 5, and in the detecting image, it is white at a position corresponding to a part of the panel where the shorting bar circuit 2 remains, and it is back at a position corresponding to a part of the panel where no shorting bar circuit 2 remains. At last, the detecting unit 7 can determine whether the shorting bar circuit 2 is cut off based on the detecting image. Specifically, when it is black at a position that corresponds to a laser cutting area 20 in the detecting image, it can be determined that the shorting bar circuit 2 is cut off.
However, in a practical detecting process, since the detecting light emitted from the image generating unit 6 lasts for a short time and is of low brightness, and meanwhile wires in the shorting bar circuit 2 are relatively thin, the effect of reflecting of the detecting light 5 by the shorting bar circuit 2 is not good, and therefore, the detecting image generated by the image generating unit 6 cannot reflect the actual situation of the shorting bar circuit 2 accurately. For example, in a situation in which some shorting bar circuits 2 are not cut off in the laser cutting areas 20, but a part of the detecting image corresponding to the shorting bar circuit 2 that is not cut off is black due to bad reflecting effect by the shorting bar circuit 2, when the detecting unit 7 judges based on the detecting image, it will be determined that no shorting bar circuit 2 remains in the area, that is, it is mistakenly detected that the shorting bar circuit 2 is cut off, thus resulting in missed detection.